Sherlock Holmes, of course, is a fictional creation—but, for a long time, the sleuth’s fans thought that his preferred method of hand-to-hand combat was fictional too. In the original Arthur Conan Doyle story The Adventure of the Empty House, Holmes returns from what readers had thought was his death at the end of The Final Problem; he explains to Watson that, contrary to public perception, he didn’t met his end in the treacherous Reichenbach Falls. How then, did he make his escape? Holmes explains that he fought off his arch-nemesis Professor Moriarty by using his knowledge of baritsu, a form of Japanese wrestling.

When she first read that story, Holmes fan and martial artist Rachel Klingberg was skeptical, having never heard of the word. She assumed that Doyle made it up, even though that was unusual for the author. That’s the same assumption that had been made for decades after the 1905 publication of the story. And she was partially right: while Doyle didn’t make up the word, he (intentionally or not) misspelled the word to make it almost unidentifiable. The correct spelling is: Bartitsu, with two Ts. And it’s a fighting style developed, improbably, in Victorian England.

That Bartitsu is real was made very clear on a recent afternoon in New York, when the Bartitsu Club of New York City met for a lesson. Klingberg discovered the existence of Bartitsu in 2006, and founded the club in 2011. “It was pretty exciting for me to think that something was fictional, and find out it’s real,” she says.

She’s not alone in discovering the style of combat—which combines stick fighting, boxing and judo—in recent years. And while the combat style was known to Holmes connoisseurs for years, the Internet helped spread the word. And interest has only grown.

Another contributor to the growth of bartitsu has been its natural synergy with the steampunk subculture, which is also growing. Roxanne Henkle, a steampunk fan who had never practiced Bartitsu before, had traveled to New York from Jacksonville, Fla., not so long ago to attend a multi-day workshop. Henkle, a Holmes fan, was also interested in learning some self-defense techniques. “I thought instead of seeing a show I could learn something,” she said, “and maybe apply it in the real world.”

Whether it’s self-defense or steampunk, historical interest or the chance to swing a walking stick around, meeting people or getting a workout—the bartitsu practitioners had their own reasons to be interested. And Rachel Klingberg says some new reasons may be coming soon, bringing new people to the world of Bartitsu: both Sherlock Holmes: A Game of Shadows and the most recent finale of the BBC’s Sherlock left off with Holmes at Reichenbach Falls. When both franchises return, they’ll have to explain how he survived.

“We’re all curious to see how he gets out,” says Klingberg, “and if we’ll see some bartitsu.”